The Nantucket Health Department announced it will begin publishing PFAS well‑testing results in town property files and posted a map showing where the department’s voluntary and private‑well samples exceed Massachusetts’ reportable concentration.

Andrew Shapiro, Health Department staff, told the Board of Health that MassDEP has assigned a release‑tracking number for the island‑wide PFAS investigation and that MassDEP recommended the local analyses use the state reportable concentration of 20 nanograms per liter (ng/L) for the PFAS‑6 sum. Shapiro said the department found more than 100 previously unreviewed MassDEP samples during coordination with state staff.

Shapiro said the health department has received 84 voluntary/private‑well samples to date. In that dataset, 61% were nondetects and seven samples (about 8%) exceeded the state PFAS‑6 reportable concentration of 20 ng/L; the maximum detected concentration in that dataset was 43 ng/L. Shapiro emphasized the map shows heterogeneity—nondetects, low‑level detects, and higher detections can occur within the same small area.

Shapiro described MassDEP procedures: detections above 20 ng/L must be reported to MassDEP; if MassDEP verifies a result above the imminent‑hazard threshold of 90 ng/L it will work to identify immediate alternate water sources and arrange access agreements to sample neighbors (the department said access agreements are typically pursued out to about 500 feet in immediate hazard cases).

Board members and public commenters raised concerns about public notification and clinical follow‑up. Board member Meredith urged broad, proactive outreach noting vulnerable groups (infants, pregnant people) and asked whether clinicians could receive CME materials on PFAS exposure and guidance for patient counseling. Public commenter Meredith also argued that there is no safe PFAS level and urged the department to alert neighbors even for low‑level detections. Shapiro said the department will publish sampling results in the property files and is working on a schedule to update the public map; the department will prioritize posting results above 20 ng/L immediately and update other results on a regular cadence.

Shapiro said EPA’s new national maximum contaminant level (MCL) addresses PFOA and PFOS individually at 4 parts per trillion (ppt) while Massachusetts sets a 20 ppt reportable concentration for the PFAS‑6 sum; he noted the two standards are not directly comparable because they regulate different compound lists and the EPA method weights individual PFAS by toxicity. Shapiro also urged continued state regulation of PFDA and PFHpA—compounds the EPA’s MCL does not include.

The board asked staff to coordinate with clinicians and community stakeholders on outreach materials; Shapiro said he will meet with a local PFAS action group and expects to publish the property‑files evidence and update the public map promptly. No new regulatory action was taken Monday.